[robjimerson]

What tire size would work best for my f32 m-sport as I am looking to change to 19" rims

[Billfitz]

Ask here:
https://f30.bimmerpost.com/forums/fo...play.php?f=423

FWIW 19s will ride harder and noisier, not handle as well and be more easily damaged than 18s.

[Onizukachan]

I did 235/40/19. Only lost 1/4” sidewall. Ride much better and quieter than the RFs.

[Billfitz]

I agree that go flats ride better and quieter than run flats. I'm liking my Michelin CrossClimate 2 much better than the original Continentals. But if you live north of the Mason-Dixon line, where potholes in spring can resemble the Grand Canyon, less than a 45 aspect ratio is begging for tire, wheel and suspension damage. There are areas where the road conditions are so bad that even in mid summer you can't find a hundred feet of smooth pavement. Rim repair shops in New York City never run out of customers.

[Onizukachan]

Depends on section width Bill.

I lost a noticeable 1/2” sidewall going to 19s from 18s, right?

Except I didn’t. 235/40/19 are 1/2” taller than OEM 225/45/18. So I lost only a 1/4” of sidewall.


He has the 19s already and a very aggressive flush offset, so if he goes with a 225/45 series tire, he’s going to have a tire an inch too tall.

But a 235/40 will fit (I know and I have it) and still have the needed cushion and the needed clearance to fender under full travel and full lock. The angle of the sidewall when mounted matches the factory inner lip profile so combined with the natural camber increase, it literally can not hit despite being flush.

Much better solution IMO than going to a 245/35 all around which far more popular but is a 1/4” inch shorter in overall height… meaning you lose 3/8” of side wall. Or a 235/40 which is half inch too short meaning you lose 3/4” of sidewall.


Ultimately though it’s up to him to decide what works best, but plus 1 to 19s are not magically some sort of horrible or even poor ride.
Anymore than the 18s were. Or 17s were 20 years ago.

Especially if you are reasonable with retire sizing and tire choice.


General rule of thumb I’ve found to be true over the last 20 years, assuming same size,
Soft to hard sidewalls by brand

Hankook, continental, Michelin/ nitto , Bridgestone.

My 235/40/19s on continental ride quieter and better than 245/40/18s did on Bridgestone potenza RE, and in wagons, the noise is much more apparent than sedans or even grandcoupes.
I have to say though the stiffer sidewall on the Bridgestone meant they felt like they handled better in dry but I sincerely doubt that they really did. They were much less forgiving


I hope this has been an enlightening discussion OP.

[J555]

235/40/19 is the best.